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Category Archives: Green Vehicles

In many ways the concept of hydrogen fuel cells being used to power cars and other vehicles has been around as long as the idea of electric powered vehicles. This is a concept which is great in theory but one which is proving a little difficult to perfect in practice. As with electric powered cars hitting the mass market, we have seen a number of false dawns with regards to hydrogen fuel cells although some experts do believe they are the next revolution in fuel power.

What exactly is a fuel cell?

In simple terms a fuel cell is able to generate electricity via a chemical reaction between hydrogen and oxygen. In order to visualise a fuel cell if you think of it as a traditional battery with a positive and negative points this should put it in perspective. The main difference is that traditional batteries store the chemicals within the cell whereas a fuel cell relies on a constant flow of fuel. The more common fuel cell relies upon hydrogen as the fuel, which reacts with the oxygen in the atmosphere to create electricity.

One of the major challenges for those pursuing fuel cell technologies is the fact that a lot of fuel cells are required to power a vehicle. In layman’s terms, a single fuel cell will give a similar amount of power to that provided by a single cell dry battery. You can imagine the number of fuel cells required to power a vehicle?

Using fuel cells to power vehicles

There are already some fuel cell powered vehicles available today which include the Toyota Mirai and the Honda Clarity FCV. Instead of petrol or diesel creating the energy to power the vehicles engine, layer upon layer of fuel cells are used to create electricity which is then used to power the engine. The engine is obviously slightly different to that powered by petrol/diesel and in this day and age one of the more eye-catching benefits is the waste produced. A traditional internal combustion engine creates an array of harmful emissions which are pumped into the atmosphere. The waste product created by the chemical reaction between hydrogen and oxygen is simply heat and water. Therefore, there is little impact upon the environment.

The most popular types of fuel cell used to power vehicles today include proton exchange and polymer exchange membranes. As we touched on above, they are structured in a similar manner to a traditional battery with a positive and negative terminal and electrolyte separating the two. It is possible to create a continuous power flow by ensuring the fuel cells have a constant supply of hydrogen which naturally reacts with the oxygen in the air. To visualise this, a traditional battery contains all of the chemicals used to create the power after which time it is “dead”. So, as the fuel cells are able to accommodate a constant flow of hydrogen they never “die”. One of the main challenges is ensuring a constant flow of hydrogen – although other substances are used in alternative fuel cells.

The benefits of fuel cell vehicles

The benefits of fuel cell vehicles are very similar to those associated with electric vehicles. There is limited waste, they are far more efficient than petrol/diesel, require fewer moving parts on a vehicle and are significantly quieter. When you bear in mind the only waste created by a hydrogen fuel cell is water and heat this is obviously a massive improvement on the traditional petrol/diesel powered internal combustion engine. As fuel cell technology continues to improve, each cell will become more powerful, fewer cells will be required per vehicle and a move to mass market fuel cell power will become more economical.

The only downside with hydrogen fuel cells, and to a lesser extent with electric powered vehicles, is the release of harmful emissions into the atmosphere as the hydrogen fuel is produced using fossil fuels. There have also been concerns about reliability and cost issues but compared to traditional petrol/diesel powered vehicles the amount of money invested in fuel cell technology has been minuscule to date.

The future of fuel cell technology

As you might have guessed, fuel cells will be more readily available in years to come and not only used to power vehicles. Where there is a requirement for energy in the form of electricity, fuel cell power will be an option especially when the technology becomes more efficient and more cost-effective. In some ways the ongoing developments in the electric car market may well end up opening doors for fuel cell technology in years to come. Even though both electric powered vehicles and hydrogen fuel cell powered vehicles indirectly create harmful emissions they are a lot more environmentally friendly than the modern day internal combustion engine fuelled by petrol/diesel.

Some experts believe that large oil companies and traditional motoring groups are quite happy to hold back the development of hydrogen fuel cells. As we saw with the EV1 back in the 1990s, while the general public may have taken to the first mainstream electric vehicle it was not necessarily what the industry wanted. Those who followed the EV1 debacle will know that overnight General Motors recalled and destroyed all EV1 vehicles. Fuel cell technology will likely face a similar challenge in the future.